Articles with spores exhibiting antagonistic properties against pathogens and/or spores forming micro-organisms

ABSTRACT

The present invention relates to disposable absorbent articles like sanitary napkins and pantiliners, which comprise spore-forming micro-organisms and/or spores which have the ability to germinate into microorganisms which exhibit antagonistic properties against undesirable strains of microorganisms when the articles are in use. The invention provides storage-stable disposable absorbent articles which can be worn for long periods of time with reduced generation of undesirable odors and enhanced fluid (e.g., bodily fluid) control within the articles.

FIELD OF THE INVENTION

This invention relates to an article, such as a disposable absorbentarticle, intended to be brought into contact with a user's skin, forexample the skin in the perineum, this article comprising spores whichin their living form exhibit antagonistic properties against undesirablestrains of micro-organisms and/or spore-forming micro-organismsexhibiting antagonistic properties against undesirable strains ofmicro-organisms.

BACKGROUND OF THE INVENTION

Hygiene articles like pantiliners, sanitary napkins, tampons, diapersand so on are used to absorb/retain bodily discharge. A problemassociated with bodily discharge (vaginal discharge including vaginalfluids, and/or menstruation, urinal discharge, faeces or perspiration)is the generation of undesirable odors within such hygiene articles thathave the tendency to escape out of the articles.

Many products and articles are available which aim to prevent theoccurrence of malodours and/or to avoid and minimise the detection ofmalodours typically associated with bodily discharge.

Various odour control materials have been disclosed in the art to combatsome of the unpleasant odours associated with body fluid discharges.Indeed solutions have been provided that use different technicalapproaches like masking, i.e., covering the odour with a perfume, orabsorbing the odour already present in the bodily fluids and thosegenerated after degradation, or preventing the formation of the odour.

Most of the focus in the prior art is found on the odour absorptiontechnology. Examples of these types of compounds include activatedcarbons, clays, zeolites, silicates, absorbing gelling materials,starches, cyclodextrine, ion exchange resins and various mixture thereofas for example described in EP-A-348 978, EP-A-510 619, WO 91/12029, WO91/11977, WO 89/02698, and/or WO 91/12030. All of these types of odourcontrol agents are believed to control odour by mechanisms whereby themalodorous compounds and their precursors are physically absorbed by theagents and thereby hinder the exit of the odour from articles likeabsorbent articles. However, such mechanisms are not completelyeffective as the formation of the odour itself is not prevented and thusodour detection is not completely avoided. Also the drawback with theseodour-absorbing agents is that, the bacteria are still able to grow, andthe use of bacteria inhibiting agents, which are often selective, cancreate risks, for instance, in the form of allergenic properties ornegative ecological consequences when handling waste. Furthermore, theuse of bacteria inhibiting agents involves the risk that resistantstrains will occur.

It is known within the medicine and foodstuff technologies to usebioconservation with the aid of bacterial antagonism as a conservingmethod, and to inoculate special bacteria strains to favourize bacteriapopulations that are beneficial to the stomach and intestines, forhealth-promoting purposes. Examples in this respect are conventionalyogurt and soured milk, and also novel bioactive foodstuffs. Thismethodology also includes the use of bacteria such as so-calledprobiotic bacteria as a substitute for antibiotic bacteria.

International Patent Application WO 92/13577 describes a tampon orsanitary napkin that has been impregnated with a culture of lactic-acidproducing bacteria, preferably of the genus Pediococcus, isolated fromhealthy individuals. The tampon or sanitary napkin is intended for theprophylactic treatment of urogenital infections. WO 97/02846 disclosesan absorbent article with antagonistic microorganisms selected from thefamily Lactobacillaceae, preferably from the genera Lactobacillus orLactococcus.

However, the problem encountered with such articles of the prior art isthe stability of the articles both during storage and use. None of theseprior art documents discloses anything about providing articles,especially disposable absorbent articles, which exhibit antagonisticproperties against undesirable pathogens, which articles can be storedfor a long time and still contain a sufficient amount of active andtransferable bacteria. It is absolutely necessary that consumer productssuch as disposable absorbent articles can be stored for a long time andunder non-ideal conditions without risking that the quality of thearticles is impaired. Consequently, there is a need for articlesdelivering antagonistic properties against pathogens, which articles arespecially adopted for long-time storage under unfavorable conditions andfor maintaining their antagonistic properties against pathogens in use.

An attempt has been made in this direction in WO 99/17813 whichdiscloses absorbent articles with a suspension of lactic acid bacteriafrom the genera Lactobacillus, Lactococcus or Pediococcus, the articlebeing dried after application of the suspension, to a moisture contentof less than 10% calculated as percentage of weight of the absorbentcore in the article. However such articles do not fully meet theproblems mentioned herein before. Also the production of such articlesrequires an extra drying step which impairs on the manufacturingrequirements of speed and cost.

The object of the present invention is to provide an article forexternal application to a human or animal, without permitting pathogenicmicroorganisms to grow or to become active to an extent such as topromote undesirable odours.

More particularly, it is an object of the present invention to providedisposable absorbent articles which deliver a broader spectrum of odourcontrol mainly by preventing the formation of malodours while notcompromising on the overall protection delivered by such articles oreven improving protection (e.g., reducing wet through and/or reducingre-wetting).

It is a further object of the present invention to provide such articleswhich are stable over prolonged time of storage without risking that thequality of the articles is impaired.

Yet, it is a further object of the present invention to provide articleswhich deliver a sustained antagonistic effect against undesirablestrains of microorganisms. More particularly it is an object of thepresent invention to provide articles, especially disposable absorbentarticles, which deliver a sustained odour control over prolonged usetime of the articles, i.e., a long lasting odour control by preventingthe formation of odour over prolonged wearing time of the articles.

Finally, it is an object of the present invention to provide articles,especially disposable absorbent articles, having the benefits mentionedherein before while meeting the requirements of ease of manufacturing,time effectiveness and cost effectiveness.

These objects have been achieved in accordance with the presentinvention by providing a disposable article comprising an absorbent corecontaining spores which are able to germinate under favorable conditions(typically in use conditions, e.g., when the article is applied to theexternal surface of a human or animal) in microorganisms (i.e., thecorresponding living form of the spores) which exhibit antagonisticproperties against undesirable strains of microorganisms, typicallypresent or arisen in the article upon contact with bodily fluids.

The living form of the spores have an activity such as to restrain thegrowth of undesirable strains of microorganisms or establishing of newundesirable species of microorganisms. Even some killing ofmicroorganisms of undesirable species may occur. Indeed, the living formof the spores used in the present invention have the ability to inhibitundesirable strains of micro-organisms by competing for substrate. Theantagonistic properties of the living form of the spores used herein isfurther partly denoted their ability of producing different so calledantimetabolites, such as lactic acid, lactoperoxidases, bacteriocins andcarbon dioxides.

More particularly, it has been surprisingly discovered that the use, inthe absorbent core of an disposable absorbent article, of spores ofmicro-organisms which exhibit antagonistic properties againstundesirable pathogens (preferably B coagulans spores also called hereinafter L. sporogenes), provides an effective odour controlling articlewhich can be stored for long time periods before its actual use, withoutrisking that the odour control ability of the article in use isimpaired. The use of these spores able storage stability upon prolongedperiods of time up to the time the article is used, i.e., is applied onthe external surface of a human or animal body where it typically comesinto contact with bodily fluids, and undergoes environmental changesthat will create favourable environmental condition for the germinationof the spores. In use conditions, for example when a disposable articleis applied onto the skin or in the urogenital zone, the bodytemperature, the micro-environmental humidity and the availability ofnutriments like menses, vaginal discharge, urine, perspiration and thelike, will allow transformation/germination of the spores (dormant form)in the microorganisms (living form).

Advantageously, the spore-containing articles according to the presentinvention retain their whole antagonistic properties against pathogenslike the odour control capacity up to the time their are used. Thus thepresent invention also allows to provide articles with effectiveantagonistic properties, e.g., odour controlling ability, while usingreduced total amount of active material (typically odour controlmaterial). Indeed a reduced total amount of spores according to thepresent invention is needed to obtain a given odour control activity fora given disposable article as compared to the total amount of non-sporeforming antagonistic micro-organisms like Lactobacillus, Pediococcus, orLactococcus that would be needed to get the same activity.

In one aspect of the present invention the disposable absorbent articlewill comprise within its absorbent core spore-forming microorganisms(living form of the microorganisms) exhibiting antagonistic propertiesagainst undesirable strains of microorganisms as an alternative or inmixture with the spores described herein.

Advantageously the spore-forming micro-organisms able to exhibitantagonistic properties against pathogens used herein, preferably thespecies B. coagulans, have the ability to create very quickly anenvironment that is not suitable for the growth of pathogens. This isdue to the rapid growth, high yield and reproducibility of suchmicro-organisms in comparison to non-spore forming bacteria likeLactobacillus acidophilus. The spore forming micro-organisms used hereinare able to survive longer and reproduce themselves in comparison to nonspore-forming micro-organisms. In other words, by the formation ofspores these micro-organisms can germinate and re-germinate in timesequence in line with the bodily fluid discharge (growth media) into anabsorbent article, thereby ensuring long-lasting antagonistic propertiesagainst pathogens.

Without to be bound by theory, it is speculated herein that in the eventwhere the bodily fluid discharge is reduced and hence less substrate isavailable for the micro-organisms, the micro-organisms used herein havethe ability to be transformed in a dormant form, i.e., spore form, whichwill be activated again upon availability of further substrate,typically upon further bodily fluid discharge. Thus also when providingthe disposable absorbent articles with the living form, i.e. the sporeforming micro-organisms, effective antagonistic properties, e.g., odourcontrolling ability, while using reduced total amount of active material(typically odour control material).

It is an advantage of the present invention to provide a disposableabsorbent article which can be worn for a relatively long period of timewithout microorganisms being allowed to grow to an extent in whichundesirable odours are generated. Advantageously the genetic identity,the lactic acid producing ability, the viability as well as the valuableantagonistic properties against pathogens are maintained even uponprolonged periods of use, typically during the whole wearing time of thearticle, e.g., up to 1 hour to 10 hours as need arises.

A further advantage associated with the disposable absorbent articles ofthe present invention (e.g., pantiliners or pads) comprising within theabsorbent core a spore-forming antagonistic microorganism and/or thespores thereof (dormant form of the micro-organisms), is a betterprotection as well as better feeling and more acceptable cleanness levelin use. Indeed, it has further been found that the spore formingmicroorganism and/or spores described herein, allow gelification of thebodily fluid discharge upon contact therewith, thereby facilitatingfluid control into the article. Indeed the presence of the spore formingmicroorganisms and/or spores in the absorbent core of the absorbentarticle by changing the physical properties of the bodily fluiddischarge enhances the fluid control properties of the article. Suchgelification will have the benefits of retaining the bodily fluid withinthe absorbent core thereby reducing the rewetting of the topsheet and/orthe soiling through as might otherwise result from squeezing the articlefor example as a consequence of legs movement of a person wearing thearticle.

Whereas the present invention is preferably directed to disposablearticles like pantiliners, feminine napkins, incontinent pads, diapers,tampons, interlabial pads, perspiration pads, surgical pads, breastpads, human or animal waste management devices and the like, otherarticles may include the spores as described herein and/ormicro-organisms too for the purpose of malodours control. Indeed, otherapplications include other articles designed to be worn in contact withthe external surface of a human or an animal such as clothing, bandages,thermal pads, acne pads, cold pads, compresses, surgical pads/dressingsand the like, body cleansing articles like impregnated wipes (e.g. babywipes, wipes for feminine intimate hygiene), articles for absorbingperspiration such as shoe insoles, and articles for animals like littersand the like.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further described with reference to the accompanyingdrawing.

FIG. 1 shows a cross sectional view of a pantiliner having an absorbentcore comprising three cellulose tissue layers, the spores beingincorporated between the first and second tissue layers.

SUMMARY OF THE INVENTION

The present invention relates to a disposable absorbent articlecomprising an absorbent core comprising at least a spore which has theability to germinate into a micro-organism which exhibits antagonisticproperties against undesirable strains of microorganisms, typicallypresent or arisen in the article and/or at least a spore-formingmicro-organism exhibiting antagonistic properties against undesirablestrains of micro-organisms

The present invention also encompasses the use, in an article,preferably a disposable article, of spores which have the ability togerminate into microorganisms which exhibit antagonistic propertiesagainst undesirable strains of microorganisms, for effective odourcontrol.

The present invention further encompasses the use, in an article,preferably a disposable article, of spores which have the ability togerminate into microorganisms which exhibit antagonistic propertiesagainst undesirable strains of microorganisms, for long lastingantagonistic properties under favourable condition, e.g., for longlasting odour control of the article in use (for instance when worn inthe urogenital zone).

The present invention further encompasses the use, in an article,preferably a disposable absorbent article, of spore-formingmicroorganisms exhibiting antagonistic properties against undesirablestrains of microorganisms, preferably B. coagulans, for long lastingantagonistic properties against undesirable strains of micro-organisms,typically for long lasting odour control of the article in use (forinstance when worn in the urogenital zone).

The present invention yet encompasses the use, in an article, preferablydisposable absorbent article, typically the absorbent core of thearticle, of spore-forming microorganisms exhibiting antagonisticproperties against undesirable strains of microorganisms and/or sporesthereof, preferably B. coagulans, for enhanced fluid control uponcontact with fluid typically bodily fluid.

DETAILED DESCRIPTION OF THE INVENTION

In one aspect the present invention relates to articles particularlysuitable for external application to a human or animal which comprisespores which have the ability to germinate into micro-organisms whichexhibit antagonistic properties against undesirable strains ofmicro-organisms and/or spore forming microorganisms exhibitingantagonistic properties against undesirable strains of microorganisms.

By “article” it is meant herein any tridimentional solid material beingable to receive/carry spores as described herein. By “article suitablefor external application to a human or animal”, it is meant any articlesuitable to be applied or worn in contact with the body of e.g., a humanincluding especially the skin and the urogenital zone. Vaginalapplication (e.g., tampon) is considered external according to thepresent invention. The term ‘disposable’ is used herein to describearticles which are not intended to be launched or otherwise restored orreused as an article (i.e., they are intended to be discarded after asingle use and, preferably to be recycled, composted or otherwisedisposed of in an environmentally compatible manner).

Preferred articles according to the present invention are disposableabsorbent articles that are designed to be placed against or inproximity to the body of a wearer and to absorb and/or containfluids/exudates discharged from the body, such as pantiliners, sanitarynapkins, catamenials, incontinence inserts/pads, diapers, tampons,interlabial pads/inserts, breast pads, human or animal waste managementdevices and the like. Typically such human urine or faecal managementdevices comprise a bag having an aperture and a flange surrounding theaperture for preferably adhesive attachment to the urogential areaand/or the perianal area of a wearer. Any faecal or urine managementdevice known in the art is suitable for use herein. Such devices aredescribed in for example WO 99/00084 to WO 99/00092. Other articlessuitable according to the present invention also include other articlesdesigned to be worn in contact with the body such as clothing, bandages,thermal pads, acne pads, cold pads, compresses, surgical pads/dressingsand the like, articles for absorbing perspiration such as shoe insoles,shirt inserts, perspiration pads and the like, body cleansing articleslike impregnated wipes (e.g. baby wipes, wipes for feminine intimatehygiene), impregnated tissues, towels, and the like, and articles foranimals like lifters and the like.

By “bodily fluids or discharges” it is meant herein any fluid producedby human or animal body occurring naturally or accidentally like forinstance in the case of skin cutting, including for instanceperspiration, urine, menstrual fluids, faeces, vaginal secretions andthe like.

As an essential element the articles of the present invention compriseat least a spore which germinates in a micro-organism which exhibitsantagonistic properties against undesirable strains of microorganisms,typically present or arisen in the article and/or a spore formingmicro-organism exhibiting antagonistic properties.

The spores also called endospores to be used herein are the dormant formof spore-forming micro-organisms (living form) which exhibitantagonistic properties against undesirable strains of micro-organisms.The use of the spores are preferred herein as they both providestability benefits during use but also during storage (i.e. prior actualuse of the articles).

The microorganisms to be used herein have the ability to survive inhostile environment in spore form (dormant form). Sporulation is thedevelopment in microorganisms of bodies each wrapped in a protectivecoat (a natural process of microencapsulation in a calcium-dipicolinicacid-peptidoglycan complex). Under favorable conditions, the sporesgerminate into viable bacilli (living form) and carry on their lifeactivities.

These spores/endospores to be used herein are heat-resistant, dehydratedresting cells that are formed intracellularly and contain a genome andall essential metabolic machinery. The spores are encased in a complexprotective spore coat.

Suitable spore-forming antagonistic microorganisms for use hereininclude the microorganisms combining the advantage of producing spores(also called endospores) which corresponds to the dormant form of themicroorganisms together with the advantage of releasing antagonisticmetabolites mainly lactic acid. Micro-organisms for use herein per se orwhich are able to form such spores for use herein belong to the genusBacillus and are typically selected from the group consisting ofBacillus coagulans (also called Lactobacillus sporogenes), Bacillussubtilis, Bacillus laterosporus and Bacillus laevolacticus. Othermicroorganisms for use herein are those belonging to the genusSporolactobacillus, more particularly the species Sporolactobacillusinulinus. Highly preferred herein is the species B. coagulans (alsocalled L. sporogenes).

L. sporogenes was first isolated from green malt and described in 1933by L. M. Horowitz-Wlassowa and N. W. Nowotelnow. It was submitted as L.sporogenes in the fifth edition (1939) of ‘Bergey's manual ofDeterminative Bacteriology’ as well as mentioned in recognizedscientific publication, Korean J. Appl. Microb. & Bioengin. (1985)13:185–190, J. Pharmaceut. Soc. Korea (1977) vol XXIII, Feb. 1, 473–474.L. sporogenes was transferred to Bacillus coagulans in the seventhedition of ‘Bergey's manual of Determinative Bacteriology’ due tosimplification in cataloguing. However in honour of the originaldiscoverers the name L. sporogenes is still used widely. Reference isalso made to the taxonomical classification of Sporolactobacillus inL'integratore Nutrizionale 2 (1) 1999, Stabilita' di integratori conSporolactobacillus, classificazione tassonomica by L. Marossi and all.

According to the Eighth Edition of Bergey's Manual of DeterminativeBacteriology, “various spore-bearing rods which produce lactic acid, arefacultative or aerobic and catalase positive, have generally andcorrectly been assigned to the genus Bacillus'. The characteristics of Bcoagulans as cited in ‘Bergey's Manual of Determinative Bacteriology’(seventh edition) and other sources are “non pathogenic gram positivespore-forming bacteria (rods 0.9 by 3.0 to 5.0 micron size), aerobic tomicroaerophilic, producing L (+) lactic acid (dextrorotatory) inhomofermentation conditions”. B coagulans also releases othermetabolites like carbon dioxide, diacetyl, bacteriocins,lacto-peroxidase. It has been isolated from natural sources, such asheat-treated soil samples inoculated into nutrient medium (Bergey'sManual of Systemic Bacteriology, Vol. 2, Sneath, P. H. A. et al., eds.,Williams & Wilkins, Baltimore, Md., 1986).

Since B. coagulans (also called L. Sporogenes) exhibits characteristicstypical of both genera Lactobacillus and Bacillus, its taxonomicposition between the families Lactobacillaceae and Bacillaceae has oftenbeen discussed. This along with the fact that there is no universallyaccepted official classification leaves room for controversy in thenomenclature. More information about L. sporogenes (also called hereinB. Coagulans) is available from the commercial brochure 69/107,incorporated herein by reference, of Sochim International s.p.a. Milano,a supplier of the spore form of L. Sporogenes.

There are a variety of different bacillus species, including, but notlimited to many different strains available through commercial andpublic sources, such as the American Tissue Culture Collection (ATCC).As already said some authors refer to Bacillus coagulans as L.sporogenes. Bacillus coagulans Hammer deposited as Lactobacillussporogenes by Kabushiki Kaisha Naruse Fermentation Research Laboratoryis commercially available under ATCC number 31284 (Internet informationsource: http://www.atcc.org/). Bacillus coagulans strains are furtheravailable as ATCC Accession Numbers 15949, 8038, 35670, 11369, 23498,51232, 11014, 12245, 10545 and 7050. Bacillus subtilis strains areavailable as ATCC Accession Numbers 10783, 15818, 15819, 27505, 13542,15575, 33234, 9943, 6051a, 25369, 11838, 15811, 27370, 7003, 15563,4944, 27689, 43223, 55033, 49822, 15561, 15562, 49760, 13933, 29056,6537, 21359, 21360, 7067, 21394, 15244, 7060, 14593, 9799, 31002, 31003,31004, 7480, 9858, 13407, 21554, 21555, 27328 and 31524. Bacilluslaterosporus strains are available as ATCC Accession Numbers 6456, 6457,29653, 9141, 533694, 31932 and 64, including Bacillus laterosporus BOD.Bacillus laevolacticus strains are available as ATCC Accession Numbers23495, 23493, 23494, 23549 and 23492.

The spores for use herein are typically activated due to the presence ofsubstrate, temperature increase and pH change. The optimum growthtemperature range for the spores of B. coagulans is between 30° C. and50° C. and the optimum pH range is from 5.0 to 6.5. Thus perspiration(pH 6) and fluid discharge like menstrual fluid discharge (pH 6.5), milkdischarge (pH 6.4) and/or urine discharge (pH 6.4) will active thegermination of the spores herein.

B. coagulans spores are ellipsoidal bodies measuring 0.9 to 1.2 by 1.0to 1.7 microns. These spores are commercially available in a white togreyish powder form. B. coagulans (also called L. sporogenes) sporespowder is commercially available under the name LACTOSPORE® from SABINSACORPORATION (Sochim international s.p.a, Milano). 1 gram of LACTOSPORE®corresponds to 15*10⁹ spores and thus to 15*10⁹ cfu (colony formingunit) of B. coagulans (L. sporogenes).

It is necessary for the spores or microorganisms per se to be added inamounts which will achieve the desired effect under favorableconditions. Typically, such spores are present in the article herein ata level per article of more than 10², preferably more than 10⁴, morepreferably from 10⁵ to 10¹², more preferably from 10⁶ to 10¹⁰ and mostpreferably from 10⁷ to 10¹² cfu. This typically corresponds to a numberof spore-forming microorganisms per article which exceeds 10² cfu,preferably exceeds 10⁴ cfu, more preferably from 10⁵ cfu to 10¹² cfu,even more preferably from 10⁶ to 10¹⁰ cfu and most preferably is from10⁷ to 10¹² cfu.

In the aspect of the invention wherein the spores are used, the articlesaccording to the present invention can be stored for longer time periodbefore actual use and still contain their whole antagonistic capacity upto the time the articles are used. Indeed B. coagulans cells (in sporeform) are protected from destruction by environmental factors by thenaturally-present microencapsulation system, the spore coat. Thesespores are activated by environmental changes like pH and temperaturechanges and availability of substrate. For instance in use when thearticle is contacted with the skin or the urogenital zone of a wearer,the temperature increases (from room temperature to above 30° C.–35°C.), substrates like humidity and bodily fluid discharge are providedand the pH will be stabilized between 5.0 to 6.5, such conditions willactivate the spores germination. The spore coat imbibe water, swell andthe increased water content will cause a rise in the metabolic rate ofthe sporulated bacili. Outgrowths will begin to protrude from thespore-coats. The outgrown cells germinate and transform into viablevegetative cell (also called ‘living form’ herein). The living formbegin to proliferate multiplying rapidly. These living forms continuetheir metabolic activities producing lactic acid and other metaboliteswhich render the environmental non-conducive for the growth of harmfulpathogenic microorganisms. The germination process will be influenced bythe body discharge in the article, leading to a somehow controlledgermination process on demand. In other words all the spores will notgerminate with the same kinetic but the germination will be in relationto the body fluid discharge on the article. This will contribute tofurther prolonging the effective beneficial microbial activity.

An important advantage of the spores used according to the presentinvention is that the spores can be stored at room temperature (20°–25°C.) without loss of viability as opposed to non-spore formingantagonistic bacteria like those taken from the genera Lactobacillus orLactococcus like Lactobacillus acidophilus, Lactococcus lactis and thelike.

In another aspect of the present invention the spore formingmicroorganisms are used. The spore-forming micro-organisms, especially Bcoagulans, have the ability to create very quickly an environment thatis not suitable for the growth of pathogens. This is due to the rapidgrowth, high yield and reproducibility of such micro-organisms incomparison to other lactic acid producing bacteria like Lactobacillusacidophilus. For example B coagulans needs 30 minutes for one generationwhile L. acidophilus needs 80 minutes. Furthermore the particularity ofthese micro-organisms is that these microorganisms are spore formingantagonistic micro-organisms, i.e., they are able to survive longer andreproduce themselves in comparison to non spore-forming micro-organisms.Indeed in contrast to non-spore forming bacteria like L. acidophilus, Bcoagulans are transformed in spores (dormant form) when the substrate isreduced (in absence or reduced amount of bodily fluid discharge) andgerminate again upon further bodily fluid discharge, i.e., reproducethemselves again through the spore form. In other words, by theformation of spores these micro-organisms can germinate and re-germinatein time sequence in line with the bodily fluid discharge (growth media)into an absorbent article, thereby ensuring long-lasting antagonisticproperties against pathogens.

Indeed B coagulans cells (in spore form) are protected from destructionby environmental factors by the naturally-present microencapsulationsystem, the spore coat. Once in the spore form the microorganism has theability to be reactivated by environmental changes like pH andtemperature changes and availability of substrate, typically by furtherbodily fluid discharge. For instance in use when the article iscontacted with the skin or the urogenital zone of a wearer, substrateslike humidity, transpiration and/or bodily fluid discharge are providedupon different sequence of time and hence the spores germination cyclewill be in line with availability of the substrates. The optimum growthtemperature range for these spores is between 30° C. and 50° C. and theoptimum pH range is from 5.0 to 6.5. New fluid discharge likeperspiration (pH 6), menstrual fluid discharge (pH 6.5), milk discharge(pH 6.4) and/or urine discharge (pH 6.4) will active thegermination/re-germination of the spores. The spore coat imbibe water,swell and the increased water content will cause a rise in the metabolicrate of the sporulated bacilli. Outgrowths will begin to protrude fromthe spore-coats. The outgrown cells germinate and transform into viablevegetative cell (the microorganism in its ‘living form’). The livingform begin to proliferate multiplying rapidly. These micro-organismscontinue their metabolic activities producing lactic acid and othermetabolites which render the environmental non-conducive for the growthof harmful pathogenic micro-organisms. The germination process will beinfluenced by the body discharge in the article, leading to a somehowcontrolled germination process on demand. In other words all the sporeswill not germinate with the same kinetic but the germination will be inrelation to the body fluid discharge on the article. This willcontribute to sustain the effective beneficial microbial activity.

Malodour is generated among other by inter or extra cellular metabolicactivity which satisfy the bacteria needs for energy and proliferation.The metabolic activity aiming the production of vital oxygen, carbon andammonium sources, leads to degraded odorous compounds as by productswhich are among low molecular weight of fatty acids, amines, mercaptan,indoles, ammonium, sulfides and the like. Bacteria that cause unpleasantsmells may belong to, for example, the family Enterobacteriaceae, e.g.,Proteus mirabilis, Proteus vulgaris, Escheriachia coli and Klebsiella.

The particularities of the spores used herein is based on themicrobiological antagonism of their living form. The particularities ofthe spore forming microorganisms used herein is based on theirantagonistic properties. Although not wishing to be bound by anyparticular theory, this implies that such antagonistic microorganismsinhibit other microorganisms by competing for substrates, formingmetabolites like L (+) form of lactic acid, enzymes likelacto-peroxidases, toxins, carbon dioxide, peroxides or antibiotics,so-called bacteriocines. The spores used herein upon activation andhence corresponding microorganisms have the ability to sustain theirgrowth and reduce the patogenicity of many pathogens like ones mentionedherein before and especially Proteus, Pseudomonas, Echerichia,Klebsiella, Enterococcus, Staphylococcus, Streptococcus and Candida. Inother words there is believed to be a competitive inhibition of growthof pathogens due to superior colonization of the antagonisticmicro-organisms (also called probiotic microorgoanisms).

It is speculated that the production of lactic acid lowers the pH to4–5, thereby inhibiting the growth of putrefactive organisms like E.coli, which require a higher optimum pH (typically 6 to 7) forfavourable growth conditions. Furthermore undissociated lactic acid hasthe tendency to penetrate the membrane of pathogens, lowering theirintracellular pH and/or interfering with their metabolic processes suchas oxidative phosphorylation, thereby inhibiting the growth of suchpathogens.

Other metabolites further contribute to inhibit the growth of pathogens.For example carbon dioxide is believed to reduce membrane permeability.Hydrogen peroxide/Lactoperoxidase are believed to oxidise basic proteinsand to destroy the “enzymes factories” (ribosomes) of pathogens.Bacteriocins are proteins or protein complexes with bactericidalactivity. Indeed, bacteriocins have the ability to link to particularreceptors on the cell wall of microorganisms, thereby affecting thefunctionality of the cell wall/membranes. Bacteriocins are also able toaffect DNA-synthesis and protein synthesis.

The particularity of the spores of the spore-forming microorganismsherein is that they germinate into antagonistic microorganisms that maybe naturally occurring microorganisms that are non-toxic and do not haveany negative biological effect on humans.

One advantage afforded by the use of such antagonistic microorganisms isthat there is avoided an undesired selection pressure on the microenvironment, such as favoring potential desease-promoting microorganismsand therewith the risk of developing pathogenic strains that areresistant to antibiotics and chemopharmaceutical preparations. Since theantimicrobial system is based on a natural, biological process, there isless risk of environmental ecological and toxic disturbances.

A further important advantage associated with the spores and/ormicroorganisms according to the present invention is that they alsoprovide the disposable absorbent article into which they have beenincorporated with a better protection, better feeling and moreacceptable cleanness level. Indeed the viable form of the spores hereinhave the ability to gelify bodily fluid discharge in the article therebyretaining the discharge in its close proximity, i.e., in the core of thearticle wherein it is applied to. This results in a dry and cleantopsheet as well as in reduced wet through.

Without to be bound by theory, it is speculated that the cause of thisgelification is the denaturation of the proteins. Indeed the sporesherein upon activation/germination in their living form andspore-forming microorganisms as described herein when used per serelease lactic acid through glycogen fermentation. As proteins aresensitive to pH, the presence of lactic acid causes the soluble proteinscontained into the bodily fluid to turn into insoluble form. Thiscreates a sort of tri-dimensional net of molecules trapping globules,minerals, fats which results in the so called gelification of the bodilyfluid and hence in control/retention of bodily fluids.

Advantageously the microorganisms herein are easily cultivated, have arapid growth, high yield and are readily handled at technical handlingthereof. Furthermore in contrast to non-spore forming microorganismsbelong to the genera Lactobacillus and/or Pediococcus the microorganismsherein do not need continuous re-inoculation to maintain themicroorganisms in a given media. Indeed they are able to re-inoculatethemselves again through the spore form. These circumstances make themicroorganisms herein also more easy to handle and thus also cheaper.

The microorganisms herein when used in living form are typically used ina freeze-drying form. Their isolation process follows known routineprocesses for the isolation of pure cultures. The isolated pure culturesare then typed according to known methods, e.g., API. The microorganismsas described herein are then cultivated in a fermentor in a manner knownper se, are separated from the medium using a separator or a centrifuge,are freeze-dried in a manner known per se and ground to a fine powder.The bacterial concentrate in powder so obtained is then typically mixedwith a fermentable carbohydrate, e.g., glucose, to a desiredconcentration. Typically a final concentration of about 100–150 billionviable microorganisms per gram is obtained. Such powder is then readyfor use in the absorbent article. Alternatively in some case it ispossible to add the living bacteria to the absorbent article and thencarry out a freeze drying thereof. Another available form is alyophilized form.

In one embodiment herein wherein the living form of the microorganismsare used, the articles, typical disposable absorbent articles might bedried to a moisture content of less than 10%, preferably less than 5%and most preferably less than 1%, calculated as percentage of weight ofthe article.

Growth of B. Coagulans

The growth of various bacillus species to form cell cultures, cellpastes and spore preparations is generally well known in the art. Bcoagulans growth described herein after can readily be used for theother bacillus species. B. coagulans is aerobic and facultative, itgrowths typically in nutrient broth, pH 5.7 to 6.8 containing up to 2%(by weight) NaCl, although neither NaCl nor KCl are required for growth.It is optimally grown at about 30° C. to 55° C. and the spores canwithstand pasteurization. B coagulans can be grown in a variety ofmedia, although it has been found that certain growth conditions producea culture which yields a high level of sporulation. For example,sporulation is enhanced if the culture medium includes 10 milligrams perliter of manganese sulfate, yielding a ratio of spores (dormant form) tovegetative cells (living form) of about 80:20. In addition certaingrowth conditions produce a bacterial spore which contains a spectrum ofmetabolic enzymes particularly suited for the present invention, i.e.control of pathogen microorganisms generating malodour development.Although spores produced by these particular growth conditions arepreferred, spores produced by any compatible growth conditions aresuitable for producing a B coagulans useful in the present invention.

Suitable media for growth of B coagulans includes Nutristart 701, PDB(potato dextrose broth), TSB (tryptic soy broth) and NB (nutrient broth)all well known and available from a variety of sources. Mediasupplements containing enzymatic digests of poultry and fish tissue, andcontaining food yeast are particularly preferred. A preferred supplementproduces a media containing at least 60% protein, and about complexcarbohydrates and 6% lipids. Media can be obtained from a variety ofcommercials sources, notably DIFCO (Detroit Mich.), OXOID (Newark N.J.)BBL (Cockeyesville Md.) and Troy Biologicals (Troy Mich.).

A particularly suitable procedure for the preparation of B. Coagulans isas follows. B coagulans Hammer bacterium (e.g., ATCC# 31284) wasinoculated and grown in nutrient broth containing 5 g Peptone, 3 g Meatextract, 10–30 mg MnSO₄ and 1000 ml distilled water adjusted to pH 7.0,using a standard airlift fermentation vessel at 30° C. The range ofMnSO₄ acceptable for sporulation is 1 mg/l to 1 g/l. The vegetativecells can be actively reproduce up to 65° C. and the spores are stableup to 90° C. After fermentation, the B coagulans Hammer bacterial cellsare collected using standard methods (e.g., filtration, centrifugation)and the collected cells and spores can be lyophilized, spray dried, airdried or frozen. As described herein, the supernatant from the cellculture can be collected and used as an extracellular agent secreted byB coagulans which has antimicrobial activity useful in a formulation ofthis invention. A typical yield from the above culture is about 100 to150 billion cells/spores per gram before drying. Spores maintain atleast 90% viability after drying-when stored at room-temperature for upto seven years, and thus the effective shelf life of a compositioncontaining B coagulans Hammer spores at room temperature is about 10years.

Sources of B Coagulans

Purified B coagulans bacterium are available from the American typeCulture Collection (Rockville, Md.) using the following accessionnumbers: B coagulans Hammer NRS T27 (ATCC# 11014), B coagulans Hammerstrain C (ATCC# 11369), B coagulans Hammer (ATCC # 31284) and Bcoagulans Hammer NCA 4259 (ATCC# 15949). Purified B coagulans bacteriumare also available from the Deutsche Sammlung con Miroorganismen undZellkuturen GmbH (Braunschweig, Germany) using the following accessionnumbers: B coagulans Hammer 1915^(AL) (DSM#2356), B coagulans Hammer1915^(AL) (DSM#2383, corresponds to ATCC#11014), B coagulans Hammer^(AL)(DSM#2384, corresponds to ATCC#11369) and B coagulans Hammer^(AL)(DSM#2385, corresponds to ATCC# 15949). B coagulans Bacterium can alsobe obtained from commercial suppliers such as Sabinsa Corporation(Piscataway,N.J.) Sochim International s.p.a. (Milano, Italy).

These B coagulans strains and their growth requirements have beendescribed previously (Baker et al, Can.J.Microbiol. 6:557–563, 1960,Blumenstock, “Bacillus coagulans Hammer 1915 und andere thermophile odermesophile, sauretolerante bacillus-Arten-eine taxonomische Untersuchung'Doctoral thesis, Univ. Goffingen, 1984, Nakamura et al, Int. J. Syst.Bacteriol, 38:63–73, 1988). Strains of B coagulans can also be isolatedfrom natural sources (e.g., heat-treated soil samples) using well knownprocedures (Bergey's Manual of Systemic Bacteriology, Vol. 2, p. 1117,Sneath, P. H. A. et al, eds, Williams &Wilkins, Baltimore, Md., 1986).

Further description of Bacillus species of interest, namely B coagulansand properties thereof can be found in WO 98/47374 to Ganeden Biotech.Inc, incorporated herein by references.

Optional Agents

The articles according to the present invention may further comprise ontop of the spores described herein before and/or micro-organismsdescribed herein before, other conventional agents or mixtures thereof.

Absorbent Gelling Materials

As is well-known from recent commercial practice, absorbent gellingmaterials (sometimes referred to as “super-sorbers”) are becomingbroadly used in absorbent articles. AGM's are materials which havefluid-absorbing properties.

Such materials are highly preferred herein due to their dual function ofabsorbing fluids and odors.

Such materials form hydrogels on contact with water (e.g., with urine,blood, and the like). One highly preferred type of hydrogel-forming,absorbent gelling material is based on polyacids, especially polyacrylicacid. Hydrogel-forming polymeric materials of this type are those which,upon contact with fluids (i.e., liquids) such as water or body fluids,imbibe such fluids and thereby form hydrogels. These preferred absorbentgelling materials will generally comprise substantially water-insoluble,slightly cross-linked, partially neutralized, hydrogel-forming polymermaterials prepared from polymerizable, unsaturated, acid-containingmonomers. In such materials, the polymeric component formed fromunsaturated, acid-containing monomers may comprise the entire gellingagent or may be grafted onto other types of polymer moieties such asstarch or cellulose. Acrylic acid grafted starch materials are of thislatter type. Thus, the preferred absorbent gelling materials includehydrolyzed acrylonitrile grafted starch, acrylic acid grafted starch,polyacrylates, maleic anhydride-based copolymers and combinationsthereof. Especially preferred absorbent gelling materials are thepolyacrylates and acrylic acid grafted starch.

Whatever the nature of the polymer components of the preferred absorbentgelling materials, such materials will in general be slightlycross-linked. Crosslinking serves to render these preferredhydrogel-forming absorbent materials substantially water-insoluble, andcross-linking also in part determines the gel volume and extractablepolymer characteristics of the hydrogels formed therefrom. Suitablecross-linking agents are well known in the art and include, for example,(1) compounds having at least two polymerizable double bonds; (2)compounds having at least one polymerizable double bond and at least onefunctional group reactive with the acid-containing monomer material; (3)compounds having at least two functional groups reactive with theacid-containing monomer materials; and (4) polyvalent metal compoundswhich can from ionic cross-linkages. Cross-linking agents of theforegoing types are described in greater detail in Masuda et al; U.S.Pat. No. 4,076,663; Issued Feb. 28, 1978. Preferred cross-linking agentsare the di- or polyesters of unsaturated mono-or polycarboxylic acidswith polyols, the bisacrylamides and the di-or triallyl amines.Especially preferred cross-linking agents areN,N′-methylenebisacrylamide, trimethylol propane triacrylate andtriallyl amine. The cross-linking agent will generally comprise fromabout 0.001 mole percent to 5 mole percent of the preferred materials.More preferably, the cross-linking agent will comprise from about 0.01mole percent to 3 mole percent of the gelling materials used herein.

The preferred, slightly cross-linked, hydrogel-forming absorbent gellingmaterials will generally be employed in their partially neutralizedform. For purposes described herein, such materials are consideredpartially neutralized when at least 25 mole percent, and preferably atleast 50 mole percent of monomers used to form the polymer are acidgroup-containing monomers which have been neutralized with asalt-forming cation. Suitable salt-forming cations include alkali metal,ammonium, substituted ammonium and amines. This percentage of the totalmonomers utilized which are neutralized acid group-containing monomersis referred to as the “degree of neutralization”. Typically, commercialabsorbent gelling materials have a degree of neutralization somewhatless than 90%.

The preferred absorbent gelling materials used herein are those whichhave a relatively high capacity for imbibing fluids encountered in theabsorbent articles; this capacity can be quantified by referencing the“gel volume” of said absorbent gelling materials. Gel volume can bedefined in terms of the amount of synthetic urine absorbed by any givenabsorbent gelling agent buffer and is specified as grams of syntheticurine per gram of gelling agent.

Gel volume in synthetic urine (see Brandt, et al, below) can bedetermined by forming a suspension of about 0.1–0.2 parts of driedabsorbent gelling material to be tested with about 20 parts of syntheticurine. This suspension is maintained at ambient temperature under gentlestirring for about 1 hour so that swelling equilibrium is attained. Thegel volume (grams of synthetic urine per gram of absorbent gellingmaterial) is then calculated from the weight fraction of the gellingagent in the suspension and the ratio of the liquid volume excluded fromthe formed hydrogel to the total volume of the suspension. The preferredabsorbent gelling materials useful in this invention will have a gelvolume of from about 20 to 70 grams, more preferably from about 30 to 60grams, of synthetic urine per gram of absorbent gelling material.

Another feature of the most highly preferred absorbent gelling materialsrelates to the level of extractable polymer material present in saidmaterials. Extractable polymer levels can be determined by contacting asample of preferred absorbent gelling material with a synthetic urinesolution for the substantial period of time (e.g., at least 16 hours)which is needed to reach extraction equilibrium, by then filtering theformed hydrogel from the supernatant liquid, and finally by thendetermining the polymer content of the filtrate. The particularprocedure used to determine extractable polymer content of the preferredabsorbent gelling agent buffers herein is set forth in Brandt, Goldmanand Inglin; U.S. Pat. No. 4,654,039; Issues Mar. 31, 1987, Reissue No.32,649, The absorbent gelling materials which are especially useful inthe absorbent articles herein are those which have an equilibriumextractables content in synthetic urine of no more than about 17%,preferably no more than about 10% by weight of the absorbent gellingmaterial.

The absorbent gelling materials herein before described are typicallyused in the form of discrete particles. Such absorbent gelling materialscan be of any desired shape, e.g., spherical or semi-spherical, cubic,rod-like polyhedral, etc. Shapes having a large greatestdimension/smallest dimension ratio, like needles and flakes, are alsocontemplated for use herein. Agglomerates of absorbent gelling materialparticles may also be used.

The size of the absorbent gelling material particles may vary over awide range. For reason of industrial hygiene, average particle sizessmaller than about 30 microns are less desirable. Particles having asmallest dimension larger than about 2 mm may also cause a feeling ofgrittyness in the absorbent article, which is undesirable from aconsumer aesthetics standpoint. Furthermore, rate of fluid absorptioncan be affected by particle size. Larger particles have very muchreduced rates of absorption. Preferred for use herein are absorbentgelling material s particles substantially all of which have a particlesize of from about 30 microns to about 2 mm. “Particle Size” as usedherein means the weighted average of the smallest dimension of theindividual particles.

Highly preferred absorbent gelling materials for use herein arepartially neutralized absorbent gelling material (i.e., at least 25 molepercent of monomers used to form the polymer are acid group-containingmonomers which have been neutralized with a salt forming cation). Indeedit has been found that the addition of absorbent gelling materials,especially partially neutralised absorbent gelling materials (e.g.,cross linked sodium polyacrylate with a degree of neutralization ofabout 70% and pH of about 5.7 to 6.3 as XZ9589001 from Dow Chemicals) ontop of the lactic acid producing microorganisms described herein in adisposable article according to the present invention (especially theabsorbent core thereof) results in further reduction of undesirableodours associated with bodily discharge occurrence in the article duringuse conditions. Without to be bound by any theory it is speculated thatthe absorbent gelling material, especially when partially neutralised,acts as a pH regulating substance (pH buffering agent), regulating thepH in a range from 4.5 to 6.8, preferably from 5 to 6.5), which isbeneficial with respect to the inhibition of the growth of undesirablebacteria and therewith the occurrence of undesirable odours.

Typically, the amount of absorbent gelling material particles used inthe articles herein, preferably the disposable absorbent articles, willrange from 0 gm⁻² to 150 gm⁻², preferably from 30 gm⁻² to 110 gm⁻², morepreferably from 55 gm⁻² to 85 gm⁻².

Odour Control Agents

For instance additional odour control agent or combinations thereof,known in the art for this purpose may be used herein. These agents cantypically be classified according to the type of odour the agent isintended to combat. Odors may be chemically classified as being acidic,basic or neutral.

Alternatively, the odor control agents may be categorised with respectto the mechanism by which the malodor detection is reduced or prevented.For example, odor control agents which chemically react with malodorouscompounds or with compounds which produce malodorous degradationproducts thereby generating compounds lacking odor or having an odoracceptable to consumers may also be utilized herein.

Suitable odor control agents for use herein typically include carbonates(e.g., sodium carbonate), bicarbonates (e.g., sodium bicarbonate),phosphates (e.g., sodium phosphate), sulphates (e.g., zinc and coppersulphates), carboxylic acids such as citric acid, lauric acid, boricacid, adipic acid and maleic acid, activated carbons, clays, zeolites,silicas and starches. Such odor control agents and systems are disclosedin more details hereinafter and for example in EP-A-348 978, EP-A-510619, WO 91/12029, WO 91/11977, WO 91/12030, WO 81/01643 and WO 96/06589.Alternative odor control agents are ion exchange resins such as thosedescribed in U.S. Pat. No. 4,289,513 and U.S. Pat. No. 3,340,875.Masking agents such as perfumes may also be used as odor control agentsherein.

Typically, the articles like disposable absorbent articles may comprisethe odour control agent or a mixture thereof at a level of from 0 gm⁻²to 600 gm⁻², preferably from 5 to 500 gm⁻², more preferably from 10 gm⁻²to 350 gm⁻² and most preferably from 20 gm⁻² to 200 gm⁻²

Preferred odour control agents for use herein are the odour absorbingagent or a mixture thereof. Indeed in a broadest aspect the presentinvention is based on a synergistic odour reduction by combining themwith the microorganisms/spores as described herein. Suitable odourabsorbing agents for use for this purpose include activated carbons,clays, zeolites, silicas, kieselguhr, starches, cyclodextrin, ionexchange resins and the like. Preferred herein are silicas and/orzeolites. Highly preferred herein is a mixture of silica and zeolite.

Cyclodextrin and derivatives thereof may be used as described in U.S.Pat. No. 5,429,628. Ion exchange resins may be used such as thosedescribed in U.S. Pat. No. 4,289,513 and U.S. Pat. No. 3,340,875.

Silica

Particularly suitable herein as an odor absorbing agent is silica.Silica, i.e. silicon dioxide SiO₂ exists in a variety of crystallineforms and amorphous modifications, any of which are suitable for useherein. In particular, silicas having a high surface area or inagglomerated form are preferred. Silica molecular sieves are notconsidered to be within the definition of silica as used herein.Preferably the silica is in a highly purified form such that is containsat least 90%, preferably 95%, more preferably 99% silicon dioxide. Mostpreferably the silica is silica gel having a 100% silica content.Alternatively, the silica may be provided from other sources such asmetal silicates including sodium silicate.

Zeolite

Another particularly suitable odour absorbing agent herein is zeolite.The use and manufacture of zeolite material is well know in theliterature and is described in the following reference texts: ZEOLITESYNTHESIS, ACS Symposium Series 398, Eds. M. L. Occelli and H. E Robson(1989) pages 2–7; ZEOLITE MOLECULAR SIEVES, Structure, Chemistry andUse, by D. W. Breck, John Wiley and Sons (1974) pages 245–250, 313–314and 348–352; MODERN APPLICATIONS OF MOLECULAR SIEVE ZEOLITES, Ph.D.Dissertation of S. M. Kuznicki, U. of Utah (1980), available fromUniversity of Microfilms International, Ann Arbor, Mich., pages 2–8.

Zeolites are crystalline aluminosilicates of group IA and group IIAelements such as Na, K, Mn, Ca and are chemically represented by theempirical formula:M_(2/n)O. Al₂O₃. ySiO₂. wH₂O

where y is 2 or greater, n is the cation valence, and w is the watercontent in the voids of the zeolite.

Structurally, zeolites are complex, crystalline inorganic polymers basedon an infinitely extending framework of AlO₄ and SiO₄ tetrahedra linkedto each other by sharing of oxygen ions. This framework structurecontains channels or interconnected voids that are occupied by thecations and water molecules.

The structural formula of a zeolite is based on the crystal unit cell,the smallest unit of structure, represented byM_(x/n)[(AlO₂)_(x)(SiO₂)_(y)]. wH₂O

where n is the valence of cation M, w is the number of water moleculesper unit cell, x and y are the total number of tedrahedra per unit cell,y/x usually having values of 1–5.

Zeolites may be naturally derived or synthetically manufactured. Thesynthetic zeolites being preferred for use herein. Suitable zeolites foruse herein include zeolite A, zeolite P, zeolite Y, zeolite X, zeoliteDAY, zeolite ZSM-5, or mixtures thereof. Most preferred is zeolite A.

According to the present invention the zeolite is preferablyhydrophobic. This is typically achieved by increasing the molar ratio ofthe SiO₂ to AlO₂ content such that the ratio of x to y is at least 1,preferably from 1 to 500, most preferably from 1 to 6.

In a preferred embodiment herein the article comprises silica togetherwith zeolite as the odour absorbing agents in a weight ratio of silicato zeolite in a range of from 1:5 to 5:1, preferably from 3:1 to 1:3 andmost preferably about 1:1.

Carbon Material

The carbon material suitable for employment herein is the material wellknown in the art as an absorber for organic molecules and/or airpurification purposes. Carbon suitable for use herein is available forma number of commercial sources under the trade names such as CALGON Type“CPG”, Type SGL, Type “CAL” and type “OL”. Often such material isreferred to as “activated” carbon or “activated” charcoal. Typically itis available in the form of an extremely fine, dusty particles havinglarge surface areas (200—several thousand m²/g.) It is to be understoodthat any of the “air purifying” or !“activated” carbons of commerce canbe used in the practice of this invention.

The Disposable Articles

The spores and/or micro-organisms described herein before (and optionalabsorbing gelling material and/or optional additional odor controlagent(s)) may be incorporated into a disposable article, preferablypantiliners, feminine napkins, incontinent pads, diapers, nursing pads,and the like by any of the methods disclosed in the art, for examplelayered on the core of the absorbent article or mixed within the fibresof the absorbent core.

The spores and/or micro-organisms as described herein and optionaladditional agents are preferably incorporated between two layers ofcellulose tissue. Optionally the system may be bonded between twocellulose tissue layers with, for example, a hot melt adhesive or anysuitable bonding system, as described in WO 94/01069.

In one embodiment of the present invention the spores and/ormicroorganisms as described herein and optional additional agents areincorporated in a layered structure in accordance with the disclosure ofWO 94/01069 or WO 95/17868. WO 95/17868 describes a layered structuresubstantially as described in WO 94/01069 with the exception that WO95/17868 comprises a much higher quantity of absorbent gelling materialin the intermediate layer which is between the fibrous layers (at least120 gm⁻²) that would be incorporated as an optional component in thepresent invention. The intermediate layer comprises in particular apolyethylene powder as thermoplastic material which is mixed with thespore powder. The mixture is then heated such that the polyethylenemelts and glues the laminate layers together.

Alternatively, the polyethylene powder may be replaced by a conventionalglue for instance those commercially available from ATO Findley underthe name H20-31® to glue the laminate layers and/or components together.Advantageously this method step allows to avoid the heating stepnecessary when using polyethylene powder. This might be typically usedherein in the embodiment wherein the microorganism (living form) isused.

Adhesive lines are preferably also placed on the edges of the laminateto ensure that the edges of the laminate stick and any loose componentspresent do not fall out of the laminate.

The spores and/or microorganisms described herein may be distributedhomogeneously or non homogeneously in the absorbent core. The sporesand/or microorganisms described herein may be distributed homogeneouslyor non homogeneously on the whole surface of the desired layer orlayers, or on one or several area of the surface layer/layers to whichit is positioned (e.g. central area and/or surrounding area like theedges of a layer of the absorbent core) or mixtures thereof. Thepresence of the spores and/or microorganisms described herein in thecore (also called intermediate layer which is positioned between thetopsheet and the backsheet) is preferred because the core collects,absorbs and stores/retains bodily fluids. Thus the close proximity tothe substrate (i.e. bodily fluid) contributes to improved fluid controlas well as to improved odour control. Indeed optimum inhibition of thedegradation activity by putrefactive bacteria and proliferation ofpathogens is obtained due to close proximity to the majority of theamount of bodily fluid present in a given disposable article with thespores and/or micro-organisms as described herein.

In one embodiment of the present invention the spores and/ormicroorganisms as described herein are used either together with odorcontrol agent and/or absorbent gelling materials, they are positionedsuch that at least a portion of the fluid discharge comes into contactwith said spores/microorganisms before the optional absorbent gellingmaterial (e.g., AGM) and/or optional additional odour control agent ifpresent. In particular, the spores can be located in a separate layerfrom the optional absorbing gelling material and/or optional additionalodor control agent if present. In such an embodiment thespores/microorganisms are located towards the topsheet or in thetopsheet itself (preferably the secondary topsheet) and the optionalabsorbing gelling material and/or optional additional odour controlagent are located further away from the topsheet than thespores/microorganisms. The benefits of this execution are related withthe fact that the inhibitory action by spores/microorganisms describedherein starts immediately after the contact with body fluids andcontinue in the fluids storage layer. In this way pathogensmicroorganisms causing malodor have lower possibility and time todegrade body fluids already colonized by spores/microorganism asdescribed herein typically B. coagulans.

The spores/microorganisms (freeze-dried form or lyophilized form for themicroorganisms) may be incorporated as a powder or a granulate. Whenused in a granulate or particulate form the spores/microorganisms asdescribed herein and the optional absorbing gelling material and/oroptional odor control agent may be granulated separately and then mixedtogether or granulated together.

The preferred absorbent articles according to the present invention aredescribed as follows:

Absorbent Core

According to the present invention, the absorbent can include thefollowing components: (a) an optional primary fluid distribution layerpreferably together with a secondary optional fluid distribution layer;(b) a fluid storage layer; (c) an optional fibrous (“dusting”) layerunderlying the storage layer; and (d) other optional components.According to the present invention the absorbent may have any thicknessdepending on the end use envisioned.

A Primary/Secondary Fluid Distribution Layer

One optional component of the absorbent according to the presentinvention is a primary fluid distribution layer and a secondary fluiddistribution layer. The primary distribution layer typically underliesthe topsheet and is in fluid communication therewith. The topsheettransfers the acquired fluid to this primary distribution layer forultimate distribution to the storage layer. This transfer of fluidthrough the primary distribution layer occurs not only in the thickness,but also along the length and width directions of the absorbent product.The also optional but preferred secondary distribution layer typicallyunderlies the primary distribution layer and is in fluid communicationtherewith. The purpose of this secondary distribution layer is toreadily acquire fluid from the primary distribution layer and transferit rapidly to the underlying storage layer. This helps the fluidcapacity of the underlying storage layer to be fully utilized. The fluiddistribution layers can be comprised of any material typical for suchdistribution layers. In particular fibrous layers maintain thecapillaries between fibers even when wet are useful as distributionlayers.

B Fluid Storage Layer

Positioned in fluid communication with, and typically underlying theprimary or secondary distribution layers, is a fluid storage layer. Thefluid storage layer can comprise any usual absorbent material orcombinations thereof. It preferably comprises absorbent gellingmaterials in combination with suitable carriers.

Suitable carriers include materials which are conventionally utilized inabsorbent structures such as natural, modified or synthetic fibers,particularly modified or non-modified cellulose fibers, in the form offluff and/or tissues. Suitable carriers can be used together with theabsorbent gelling material, however, they can also be used alone or incombinations. Most preferred are tissue or tissue laminates in thecontext of sanitary napkins and panty liners.

An embodiment of the absorbent structure made according to the presentinvention may comprise multiple layers comprises a double layer tissuelaminate formed by folding the tissue onto itself. These layers can bejoined to each other for example by adhesive or by mechanicalinterlocking or by hydrogen bridge bands. Absorbent gelling material orother optional material can be comprised between the layers.

Modified cellulose fibers such as the stiffened cellulose fibers canalso be used. Synthetic fibers can also be used and include those madeof cellulose acetate, polyvinyl fluoride, polyvinylidene chloride,acrylics (such as Orlon), polyvinyl acetate, non-soluble polyvinylalcohol, polyethylene, polypropylene, polyamides (such as nylon),polyesters, bicomponent fibers, tricomponent fibers, mixtures thereofand the like. Preferably, the fiber surfaces are hydrophilic or aretreated to be hydrophilic. The storage layer can also include fillermaterials, such as Perlite, diatomaceous earth, Vermiculite, etc., toimprove liquid retention.

If the absorbent gelling material is dispersed non-homogeneously in acarrier, the storage layer can nevertheless be locally homogenous, i.e.have a distribution gradient in one or several directions within thedimensions of the storage layer. Non-homogeneous distribution can alsorefer to laminates of carriers enclosing absorbent gelling materialspartially or fully.

C Optional Fibrous (“Dusting”) Layer

An optional component for inclusion in the absorbent core according tothe present invention is a fibrous layer adjacent to, and typicallyunderlying the storage layer. This underlying fibrous layer is typicallyreferred to as a “dusting” layer since it provides a substrate on whichto deposit absorbent gelling material in the storage layer duringmanufacture of the absorbent core. Indeed, in those instances where theabsorbent gelling material is in the form of macro structures such asfibers, sheets or strips, this fibrous “dusting” layer need not beincluded. However, this “dusting” layer provides some additionalfluid-handling capabilities such as rapid wicking of fluid along thelength of the pad.

D Other Optional Components of the Absorbent Structure

The absorbent core according to the present invention can include otheroptional components normally present in absorbent webs. For example, areinforcing scrim can be positioned within the respective layers, orbetween the respective layers, of the absorbent core. Such reinforcingscrims should be of such configuration as to not form interfacialbarriers to fluid transfer. Given the structural integrity that usuallyoccurs as a result of thermal bonding, reinforcing scrims are usuallynot required for thermally bonded absorbent structures.

The Topsheet

According to the present invention the absorbent article comprises as anessential component a topsheet. The topsheet may comprise a single layeror a multiplicity of layers. In a preferred embodiment the topsheetcomprises a first layer which provides the user facing surface of thetopsheet and a second layer between the first layer and the absorbentstructure/core.

The topsheet as a whole and hence each layer individually needs to becompliant, soft feeling, and non-irritating to the wearer's skin. Italso can have elastic characteristics allowing it to be stretched in oneor two directions. According to the present invention the topsheet maybe formed from any of the materials available for this purpose and knownin the art, such as woven and non woven fabrics and films. In apreferred embodiment of the present invention at least one of thelayers, preferably the upper layer, of the topsheet comprises ahydrophobic, liquid permeable apertured polymeric film. Preferably, theupper layer is provided by a film material having apertures which areprovided to facilitate liquid transport from the wearer facing surfacetowards the absorbent structure. If present the lower layer preferablycomprises a non woven layer, an apertured formed film or an airlaidtissue.

The Backsheet

The backsheet primarily prevents the extrudes absorbed and contained inthe absorbent structure from wetting articles that contact the absorbentproduct such as underpants, pants, pyjamas and undergarments. Thebacksheet is preferably impervious to liquids (e.g. menses and/or urine)and is preferably manufactured from a thin plastic film, although otherflexible liquid impervious materials can also be used. As used herein,the term “flexible” refers to materials that are compliant and willreadily conform to the general shape and contours of the human body. Thebacksheet also can have elastic characteristics allowing it to stretchin one or two directions.

The backsheet typically extends across the whole of the absorbentstructure and can extend into and form part of or all of the preferredsideflaps, side wrapping elements or wings.

The backsheet can comprise a woven or nonwoven material, polymeric filmssuch as thermoplastic films of polyethylene or polypropylene, orcomposite materials such as a film-coated nonwoven material. Preferably,the backsheet is a polyethylene film typically having a thickness offrom about 0.012 mm (0.5 mil) to about 0.051 mm (2.0 mil).

Exemplary polyethylene films are manufactured by Clopay Corporation ofCincinnati, Ohio, under the designation P18-0401 and by EthylCorporation, Visqueen Division, of Terre Haute, Ind., under thedesignation XP-39385. The backsheet is preferably embossed and/or mattfinished to provide a more clothlike appearance. Further, the backsheetcan permit vapors to escape from the absorbent structure, i.e. bebreathable, while still preventing extrudates from passing through thebacksheet. Also breathable backsheets comprising several layers, e.g.film plus non-woven structures, can be used.

Odor Control Test

The odor reduction is measured by for example an in vitro sniff test. Invitro sniff test consists in analyzing by expert graders the odorassociated with articles comprising the ingredients to be tested(including references articles) when contacted with an odourouscomponents-containing solution.

The expert graders express their judgment about (un)pleasantness of theodor using a (un)pleasantness scale, typically from −10 (highest levelof unpleasantness) to 5 (most pleasant). With this procedure, eachgrader compares MU (Unpleasantness) in the test session. The relative MUodor values from different products are assigned numbers. For example,in a test session, a sample that is perceived to be twice as strong asanother is assigned twice as large a number. One that is perceived to beone-tenth as strong as another is assigned a number one-tenth as large,etc. In each test session, zero is used to designate neutral hedonicity,and + and − numbers are assigned in ratio proportion to the relativepleasantness and unpleasantness of the odor.

Surprisingly in vitro in-house sniff tests conducted by using anodourous components-containing solution reproducing the essentialmalodorous characteristics of menses showed synergistic odor reductionwhen spores/microorganisms as described herein (e.g. B coagulans)together with odour absorbing agent (e.g., silicate available asSyloblanc 82 from Grace GmbH and/or zeolite available as Zeolite A,Wessalith CSfrom Degussa AG) to each of these ingredients taken alone atthe same total level of active. Indeed the % of unpleasantness reductionobtained for the mixture was higher than the % of unpleasantnessreduction obtained for each of the two ingredients used alone at thesame total level of active. The Unpleasantness values, for each sample,was obtained as a mean of at least 15 observations (3 products, 5graders). These results were statistically significant.

Alternatively the odor reduction can also be measured with in vivo snifftests as described in patent applications, EP-A-81 1387 or WO97/46191,herein incorporated by reference.

The present invention is further illustrated by the following example.

EXAMPLES Example A

The feminine pads used in the following examples were Always (Always isa registered Trade Mark) as sold by the Procter & Gamble Company.

Each feminine pad was opened by cutting the wrap around the perforatedcoverstock at its bottom face approximately along a longitudinal edge ofthe release paper which covers the external adhesive layer. The side ofthe absorbent fibrous core was then exposed by slightly shifting thewater impermeable plastic bottom layer and subsequently, the fibrouscore was split into two halves, each having approximately the samethickness, along a plane which is parallel to the plane of the paditself. B. coagulans spores powder was homogeneously distributed betweenthese tow fibrous layers which were then joined together to reconstitutethe absorbent core.

The water impermeable inner backsheet was then put back into itsoriginal position and the wrap around perforated coverstock was sealedalong the cut by means of e.g. a double sided adhesive tape.

Samples were produced using the method above. B. coagulans spores powderused was Lactospore® (0.7 g) commercially available from SabinsaCorporation (Sochim International S.P.A. Milano). 0.7 g of Lactospore®corresponds to about 10.5*10⁹ spores per pad (ten billions of spores perpad), i. e., about 10.5*10⁹ cfu of microorganisms per pad.

Example B

Other pads were prepared by following the method in Example A exceptthat absorbing gelling material (AGM) was added on top of the B.coagulans spores in Example A. Accordingly B. coagulans spores and AGMwere homogeneously distributed between these two fibrous layers whichwere then joined together to reconstitute the absorbent core.

B. coagulans spores powder used was Lactospore® (0.7 g) commerciallyavailable from Sabinsa Corporation (Sochim International S.P.A. Milano).The AGM (0.8 g) used was cross linked sodium polyacrylate XZ 9589001,available from Dow Chemicals.

Example C

Other pads were prepared by following the method in Example B exceptthat after having split the fibrous core into two halves, the B.coagulans spores were homogeneously distributed onto the upper halvefibrous layer (i.e., the fibrous layer halve intended to be closer tothe topsheet) and the AGM was homogeneously distributed onto the lowerhalve fibrous layer (i.e., the one intended to be closer to thebacksheet of the pad once reconstituted). Then a layer of airlaid tissue(19 mm*70 mm of low basis weight) available from Fripa under thecode/name NCB Tissue HWS was positioned between the two halve fibrouslayers which are then joined together to reconstitute the absorbentcore. The presence of the airlaid tissue between the two fibrous layeravoids direct contact between the B. coagulans spores and the AGM.

These samples were produced using as the B. coagulans spores Lactospore®(0.7 g) commercially available from Sabinsa Corporation (SochimInternational S.P.A. Milano) and AGM (0.8 g) available from DowChemicals (XZ 9589001).

Example D

The pantiliners used in the following examples were Always pantiliners(Always is a Registered Trade Mark) as sold by the Procter & GambleCompany.

Each pantiliner was opened by cutting the polyethylene (PE) perforatedfilm along a longitudinal edge of the pantiliner at its bottom face. Theupper two layers of the inner three-folded cellulose tissue sheet, whichconstitutes the absorbent core of the pantiliner, were cut away andsubstituted with two layers of cellulose air laid tissue. B. coagulanspowder was homogeneously dispersed between said two layers. The wholepantiliner structure was then reconstituted and sealed along the edgesby means of adhesive.

FIG. 1 represents a sectional view of the pantiliner structure 1 whichcomprises a topsheet 2, airlaid layers 8 joined at their longitudinaledges with adhesive lines 9, L sporogenes powder 14, a tissue layer 10,a backsheet 4, adhesive area 5, an adhesive layer 6 and a removablerelease liner 7. Indeed FIG. 1 shows an absorbent core comprised of twolayers of air laid cellulose tissue 8 joined at their longitudinal edgeswith adhesive 9 and having a layer of cellulose tissue 10 therebeneathto form a three layered absorbent core.

Samples were prepared by the method as described above, which samplesincorporate B. coagulans spores as Lactospore® (0.7 g) commerciallyavailable from Sabinsa Corporation (Sochim International S.P.A. Milano).0.7 g of Lactospore® corresponds to about 10.5*10⁹ spores per pantiliner(ten billions of spores per pad), i.e., about 10.5*10⁹ cfu ofmicroorganisms per pantiliner.

Example E

Other pantiliners were prepared by following the method in Example Dexcept that absorbing gelling material (AGM) was added on top of B.coagulans spores in Example D. Accordingly B. coagulans spores and AGMwere homogeneously distributed between these two air laid layers whichwere then joined together to reconstitute the absorbent core.

B. coagulans spores powder used was Lactospore® (0.7 g) commerciallyavailable from Sabinsa Corporation (Sochim International S.P.A. Milano).The AGM (0.8 g) used was cross linked sodium polyacrylate XZ 9589001,available from Dow Chemicals.

Example F

The feminine pads used in the following examples were Always (Always isa registered Trade Mark) as sold by the Procter & Gamble Company.

Each feminine pad was opened by cutting the wrap around the perforatedcoverstock at its bottom face approximately along a longitudinal edge ofthe release paper which covers the external adhesive layer. The side ofthe absorbent fibrous core was then exposed by slightly shifting thewater impermeable plastic bottom layer and subsequently, the fibrouscore was split into two halves, each having approximately the samethickness, along a plane which is parallel to the plane of the napkinitself. B Coagulans powder was homogeneously distributed between thesetow fibrous layers which were then joined together to reconstitute theabsorbent core.

The water impermeable inner backsheet was then put back into itsoriginal position and the wrap around perforated coverstock was sealedalong the cut by means of e.g. a double sided adhesive tape.

Samples were produced using the method above. B Coagulans powder usedwas freeze/dried commercially available under ATCC number 31284(ATCC=American Type Culture Collection). Each pad contained about 10*10⁹cfu of such microorganisms (ten billions cfu).

Example G

Other pads were prepared by following the method in Example F exceptthat absorbing gelling material (AGM) was added on top of B Coagulans inExample F. Accordingly the B Coagulans and AGM were homogeneouslydistributed between these two fibrous layers which were then joinedtogether to reconstitute the absorbent core.

B Coagulans powder used was freeze-dried powder commercially availableunder ATCC number 31284 (ATCC=American Type Culture Collection). Eachpad contained about 10*10⁹ cfu of such micro-organisms. The AGM (0.8 g)used was cross linked sodium polyacrylate XZ 9589001, available from DowChemicals.

Example H

Other pads were prepared by following the method in Example G exceptthat after having split the fibrous core into two halves, B Coagulanspowder was homogeneously distributed onto the upper halve fibrous layer(i.e., the fibrous layer halve intended to be closer to the topsheet)and AGM was homogeneously distributed onto the lower halve fibrous layer(i.e., the one intended to be closer to the backsheet of the pad oncereconstituted). Then a layer of airlaid tissue (19 mm*70 mm of low basisweight) available from Fripa under the code/name NCB Tissue HWS waspositioned between the two halve fibrous layers which are then joinedtogether to reconstitute the absorbent core. The presence of the airlaidtissue between the two fibrous layer avoids direct contact between BCoagulans and AGM.

These samples were produced using freeze-dried powder of B Coagulanscommercially available under ATCC number 31284 (ATCC=American TypeCulture Collection). The pads contained about 10*10⁹ of suchmicroorganisms.

Example I

The feminine pads used in the following examples were Always (Always isa registered Trade Mark) as sold by the Procter & Gamble Company.

Each feminine pad was opened by cutting the wrap around the perforatedcoverstock at its bottom face approximately along a longitudinal edge ofthe release paper which covers the external adhesive layer. The side ofthe absorbent fibrous core was then exposed by slightly shifting thewater impermeable plastic bottom layer and subsequently, the fibrouscore was split into two halves, each having approximately the samethickness, along a plane which is parallel to the plane of the napkinitself. The odor adsorbing agents (Silica or Zeolite or both) werehomogeneously mixed together with B coagulans powder and homogeneouslydistributed on this layer. Then all the layers were joined together toreconstitute the absorbent core.

The water impermeable inner backsheet was then put back into itsoriginal position and the wrap around perforated coverstock was sealedalong the cut by means of e.g. a double sided adhesive tape.

B. coagulans spores powder commercially available as Lactospore® (0.7 g)from Sabinsa Corporation (Sochim International S.P.A. Milano). Thus eachpad comprised about 10*10⁹ cfu of L. sporogenes. The silica (1 g) usedwas Syloblanc 82 available from Grace GmbH. The zeolite (0.8 g) used wasZeolite A, Wessalith CS, available from Degussa AG.

Alternatively other samples were prepared with B. coagulans (livingform) commercially available under ATCC number 31284 in freeze-driedform instead of Lactospore®, the samples comprising about 10⁹ cfu ofsuch microorganisms.

Example J

In Example J samples were produced using the same method as in ExampleI, except that AGM (0.8 g) available from Dow Chemicals (XZ 9589001),was added to B coagulans and odor absorbing agents (silicate or zeoliteor both).

All the above exemplified pads/pantiliners delivered outstanding odourcontrol benefits for prolonged period of time when in use, typicallywhen coming into contact with for example bodily fluids while deliveringeffective protection as well as cleanness and dryness benefit. Alsothese pads/pantiliners were able to minimize the occurrence of skinproblems. The pads/pantiliners comprising spores showed outstandingstability upon prolonged period of storage

1. A disposable article comprising a liquid pervious topsheet and abacksheet, an absorbent core being intermediate to said backsheet andsaid tonsheet; said absorbent core comprising at least a spore which hasthe ability to germinate into a microorganism which exhibitsantagonistic properties against undesirable strains of microorganisms.2. An article according to claim 1 wherein said article is a sanitarynapkin, a pantiliner, a tampon, a diaper, an incontinent pad, a breastpad, a human or animal waste management device, a perspiration pad or aninterlabial pad.
 3. An article according to claim 1 wherein thespore-forming micro-organism exhibiting antagonistic properties againstundesirable strains of micro-organisms is a species of the geniusBacillus and/or of the genius Sporolactobacillus and mixtures thereofand/or wherein the spore is of said spore-forming micro-organism.
 4. Anarticle according to claim 1, which further comprises an absorbentgelling material.
 5. An article according to claim 4 which comprise theabsorbent gelling material at a level of from 30 gm⁻² to 110 gm⁻².
 6. Anarticle according to claim 1, which further comprises an additionalodour control agent.
 7. An article according to claim 6, wherein thelevel of the additional odour control agent or mixture thereof is from 0gm⁻² to 600 gm⁻².